The present invention relates to a seat device which includes a reclining device for adjusting an angle of a seatback fixed to a frame of a seat. More particularly, the present invention pertains to a connecting construction between the reclining device and the frame of the seat of the seat device.
A known seat device including a construction for connecting a seat frame and a reclining device is disclosed in Japanese Patent Laid-Open Publication No. H10-276850. The reclining device provided on the seat device includes an upper arm, a lower arm, and a lock mechanism which can lock the relative rotation between the upper arm and the lower arm. A plurality of projections for locking are formed on a side face of the upper arm and the lower arm. A plurality of holes are formed on a seatback frame and a seat cushion frame for constructing the seat frame. The seat frame and the reclining device are connected by fitting the projections for locking into the holes respectively and by welding. An inner gear for lock mechanism is formed on either one of the upper arm or the lower arm of the reclining device so that the plural projections for locking are positioned approximate to the rotation center of the reclining device, that is the inside of the inner gear.
As shown in FIG. 4, with the known seat device having a construction that a retractor of a seatbelt is built in the seatback, the seat frame is applied with the excessive load via the seatbelt at the collision of the vehicle. Generally, the seat frame is made from the steal plate thinner than the arm of the reclining device. With the connecting construction of the seat frame and the reclining device in the known seat device disclosed in Japanese Patent Laid-Open Publication No. H10-276850, the seat frame is likely to be deformed to be broken with a smaller load compared to the reclining device when the excessive load affects the seatback. Further, with the arm formed with the inner gear for the lock mechanism of the reclining device, the projections for locking are positioned approximate to the rotation center of the reclining device. Thus, particularly large load is applied to the portion of the seat frame contacting the projections for locking, which is a weakness for decreasing the strength of the device. Although the entire plate thickness of the seat frame may be increased in order to obviate the drawback in a known seat device, another drawback that the weight of the seat device is increased is generated with this method.
A need thus exists for a seat device which has high strength of connecting portions between a seat frame and a reclining device without increasing a weight of the seat device.
In light of the foregoing, the present invention provides a seat device which includes a seat cushion frame provided in a seat cushion, a seatback frame provided in a seatback, an upper arm connected to the seatback frame, a lower arm rotatably connected to the upper arm and connected to the seat cushion frame, a lock mechanism for locking a rotation of the upper arm relative to the lower arm, a reclining device for adjusting an angle of the seatback frame relative to the seat cushion frame, a locking portion provided either one of the upper arm and the lower arm, a reinforcement member provided either on the seatback frame or the seat cushion frame opposing to said either one of the upper arm or the lower arm provided with the locking portion, and a portion to be locked provided on the reinforcement member. The portion to be locked and the locking portion are connected.
According to another aspect of the present invention, a seat device includes a seat cushion frame provided in a seat cushion, a seatback frame provided in a seatback, an upper arm connected to the seatback frame, a lower arm rotatably connected to the upper arm and connected to the seat cushion frame, a lock mechanism for locking a rotation of the upper arm relative to the lower arm, a reclining device for adjusting an angle of the seatback frame relative to the seat cushion frame, a locking portion provided on the upper arm, a reinforcement member provided on the seatback frame opposing to the upper arm provided with the locking portion, and a portion to be locked provided on the reinforcement member. The portion to be locked and the locking portion are connected.